Le cycle biologique d'Acanthocyclops robustus (G. O. Sars, 1863) (Crustacea, Copepoda, Cyclopidae) de Tunisie

The life cycle of Acanthocyclops robustus (G. O. Sars, 1863) is studied, based on material cultured from ovigerous females collected in the reservoir Bir M'cherga (Tunisia). Six nauplius, five copepodid stages and the ontogenetic changes occurring during the development are studied. The redescription of the adult male and female stages allows us to confirm some specific characters: morphology of the fourth natatory leg, shape of the seminal receptacle, presence of spinules at the insertion of the lateral and the external furcal setae, ornamentation of the distal margin of the urosomites, shape of the male sixth leg characterized by a long spine. The study of the antennulary development reveals the importance of other diagnostic characters, particularly the setation pattern of the first segment at the second and third copepoditic stages.